Lethocolea subgen. Symphyomitra (Spruce) Grolle

Gradstein, S. Robbert, Ilkiu-Borges, Anna Luiza, Cargill, D. Christine, Beckmann, Karen & Vanderpoorten, Alain, 2024, An integrative taxonomic study of the genus Lethocolea (Marchantiophyta: Acrobolbaceae), Plant Ecology and Evolution 157 (3), pp. 375-398 : 375-398

II. Lethocolea subgen. Symphyomitra (Spruce) Grolle ( Grolle 1972: 549)

Symphyomitra Spruce ( Spruce 1885: 503).

Neoprasanthus S. Winkl. ( Winkler 1969: 69) – Type species: Neoprasanthus granatensis S. Winkl. (= Lethocolea congesta (Lehm.) S. W. Arnell).

Lethocolea sect. Pachycolea R. M. Schust. ( Schuster 2021: 531) – Type species: Lethocolea glossophylla (Spruce) Grolle (= L. congesta (Lehm.) S. W. Arnell).

Type species.

Symphyomitra glossophylla Spruce (= L. congesta (Lehm.) S. W. Arnell ).

Description.

Stems ventral surface green to brownish-green, stolons present or absent. Leaf cells with a densely papillose cuticle; oil bodies 1–3 per cell (usually 2), dark brown, often persistent in plants with distinct trigones (Fig. 3 G, H ), ellipsoid to fusiform, 8–10 × 15–25 µm, brown, finely papillose, pupils (“ eye spots ”) absent. Antheridia 1 (– 6) per bract. Marsupia short-cylindrical, up to 3 mm long, wall 5–6 cells thick, marsupial canal lined by few papilliform cells ( Grolle 1972). Capsules splitting to the base into 2–4 valves, with two adjacent valves sometimes remaining partially connate. Asexual reproduction by disciform gemmae absent.

Distribution.

One species in Africa, Central and South America, and on the south Atlantic Islands.

Figures

Figure 3. Cuticle and oil bodies in Lethocolea, SEM. A, D. Papillose cuticle of L. congesta. B. Smooth cuticle of L. pansa. C. Papillose cuticle of L. javanica. E – F. Oil bodies of L. javanica. G – H. Oil bodies of L. congesta. A, D from Larrain 42566; B from Arts 129 / 11; C, E – F from Beckmann (unpublished thesis work, 1985); G – H from from Arts 19 / 54. Photos: A – B, D by Anna Luiza Ilkiu-Borges; C, E – F by Karen Beckmann; G – H by Christine Cocquyt and Robbert Gradstein.